在Symfony2中使用带有外键的Doctrine2

Question

I have a MySQL database (that is later imported into Doctrine) set up that links 3 different tables by way of foreign keys. The relationship is as follows: Many As go to one B, and many Bs go to one C. For the web page that I am trying to create, I need some of the related B's information on a page about A, while being categorized by C.

Think of it like this: A is "dog_food", B is "company", and C is "company_category". That is, on a page displaying different kinds of dog food, I need to display information about the manufacturing company; I only display those dog foods based on how the user specifies what kind of company they want to buy from.

Pulling information dynamically from A is trivial, since the repository is pulled and the rows exist as entities. Say, {{ dog_food.price }} would call (if specified in a for loop, this is Twig code) a single instance's price.

I have read about the @OneToOne, @OneToMany, etc. annotations, but have not been able to find a way to easily utilize their effects inside of a Twig template. The aggregate entities and repositories for all 3 tables exist as variables in the Controller. It should be mentioned that, continuing with this example, that there is a single companyID field in table B corresponding to multiple dog foods, and a single categoryID associated with multiple companies.

What happens if I want to list the company name above the price? How do I access that information in Doctrine, and furthermore, in Twig?

Answer 1

I will translate what you've said above into code that I would effectively write if I was you:

So, I assume that, along with the mapping you defined , your company category entity is called 'Company_category', your dog food entity is called 'Dog_food'. I would pass the id of the company_category to an action in my controller, then, I would retrieve all the companies that belong to that company_category, something like this:

public function xyzAction($id){
$companies=$this->getDoctrine()->getRepository('XYZYourBundle:Company')
                ->findBy(array('company_category'=>$id));
//Hold on I will just complete it
}

Then I would retrieve all the dog foods objects from my DB, that the company's exist in $companies, the result returned in the first line of code, to do this, I would first:

1-Define my own criteria: this would help you define a complex , powerful conditions and it's easy to use.

2-Use my criteria to filter the result of the repository, this would be useful So let's update our action:

public function xyzAction($id){

   $companies=$this->getDoctrine()->getRepository('XYZYourBundle:Company')->findBy(array('company_category'=>$id));
   $criteria = new \Doctrine\Common\Collections\Criteria();
   $criteria->where($criteria->expr()->in('company',$companies)); 
   $dogfoods=$this->getDoctrine()->getRepository('XYZYourBundle:Dog_food')->matching($criteria)      
   //Hold on I will just complete it
   }

and finally render our dogfood objects to a twig template:

public function xyzAction($id){

   $companies=$this->getDoctrine()->getRepository('XYZYourBundle:Company')->findBy(array('company_category'=>$id));
   $criteria = new \Doctrine\Common\Collections\Criteria();
   $criteria->where($criteria->expr()->in('company',$companies)); 
   $dogfoods=$this->getDoctrine()->getRepository('XYZYourBundle:Dog_food')->matching($criteria)      
   return $this->render('XYZYourBundle:test.html.twig', array(
    'dogfoods'=>$dogfoods));
   }

Now, let's place ouselves in a twig template, we're gonna iterate through our $dogfoods objects and we will display some information, assuming you defined the needed getters and setters;

  {% for dogfood in dogfoods %}
     {{dogfood.price}}        
     {{dogfood.company}}
  {% endfor %}

Edit : you can get the company's name by either:

-implement a tostring method that returns the company's name and in twig use

{{dogfood.company}}

or

-in twig, use

{{dogfood.company.name}}

Hope this helps you, if something doesn't work just tell me.